Question

What three tests are used for initial evaluation of
pulmonary function?

Answer 1

Initial pulmonary function evaluation often includes spirometry, body plethysmography, and diffusion capacity tests. Spirometry measures FEV1 and FVC, helping detect restrictive and obstructive lung diseases. Body plethysmography evaluates total lung capacity, and diffusion capacity tests for gas exchange efficiency.

Step-by-step explanation:

The three tests commonly used for initial evaluation of pulmonary function are:

1. Spirometry: This test measures lung volumes and is crucial for assessing respiratory diseases. It includes measurements such as forced expiratory volume (FEV), particularly FEV1, which is the amount of air that can be forced out in one second, and forced vital capacity (FVC), the total amount of air that can be forcibly exhaled from the lungs.
2. Body plethysmography: Often done in addition to spirometry, this test measures total lung capacity (TLC) and residual volume (RV), providing a more comprehensive evaluation of lung function.
3. Diffusion capacity: This test measures how well oxygen and other gases pass from the lungs into the blood, which can signal problems in the alveolar-capillary membrane.

The FEV1/FVC ratio is a critical component in diagnosing restrictive and obstructive lung diseases such as asthma, emphysema, and fibrosis. A high FEV1/FVC ratio suggests lung fibrosis, indicating that the lungs are not compliant, while a low ratio points to airway resistance characteristic of obstructive diseases like asthma.